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无人机舵面故障高阶滑模重构观测器设计及主动容错控制

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火力与指挥控制 2024年第4期49卷 170-176页

作者：刘勇求刘晓峰广东科技学院广东东莞523330 空军航空大学长春130000

针对无人机舵面损伤故障容错问题,提出了基于二阶非奇异终端滑模重构观测器及主动容错设计方法。在分析舵面正常偏转运动学和动力学特性基础上,构建了无人机典型舵面故障非线性特性模型。提出无人机舵面故障的高阶滑模重构滑模观测器设... 详细信息

针对无人机舵面损伤故障容错问题,提出了基于二阶非奇异终端滑模重构观测器及主动容错设计方法。在分析舵面正常偏转运动学和动力学特性基础上,构建了无人机典型舵面故障非线性特性模型。提出无人机舵面故障的高阶滑模重构滑模观测器设计方案;引入线性变换降维简化观测器设计程式;将终端滑模和非奇异终端滑模结合起来,实现滑模运动有限时间快速收敛;综合自适应律、线性矩阵不等式设计观测器系数矩阵,确保状态估计偏差有界稳定。提出集状态与故障重构于一体的主动容错控制方案,并通过仿真算例检验所提方案的有效性。

关键词：舵面故障二阶非奇异终端滑模无人机主动容错观测器

Promotion effects of salt-alkali on ammonia volatilization in a coastal soil

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Pedosphere 2024年第1期34卷 191-199页

作者： Zhenqi SHI Dongli SHE Yongchun PAN yongqiu XIA College of Agricultural Science and Engineering Hohai UniversityNanjing 210098China Jiangsu Province Engineering Research Center for Agricultural Soil-Water Efficient Utilization Carbon Sequestration and Emission ReductionNanjing 210098China Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Coastal ecosystems are highly susceptible to salt-related problems due to their formation process and geographical location. As such ecosystems are the most accessible land resources on Earth, clarifying and quantifying the effects of salt-alkali conditions on N concentration and ammonia(NH_(3)) volatilization are pivotal for promoting coastal agricultural productivity. The challenge in establishing this effect is to determine how salt-alkali conditions impact NH_(3) volatilization through direct or indirect interactions. An incubation experiment using a coastal soil from a paddy farmland, combined with the structural equation modeling(SEM) method, was conducted to reveal the net effects of salt-alkali on NH_(3) volatilization and the role of environmental and microbial factors in mutual interaction networks. The specific experimental design consisted of four salt treatments(S1, S2, S3, and S4: 1‰, 3‰, 8‰, and 15‰ NaCl by mass of soil, respectively), four alkaline treatments(A1, A2, A3, and A4: 0.5‰, 1‰, 3‰, and 8‰ NaHCO_(3)by mass of soil, respectively) and a control without NaCl or NaHCO_(3) addition(CK), and each treatment had three urea concentrations(N1, N2, and N3: 0.05, 0.10, and 0.15 g N kg^(-1) soil,respectively) and three replicates. At the N1, N2, and N3 levels, NH_(3)volatilization increased by 9.31%–34.98%, 3.07%–26.92%, and 2.99%–43.61% as the NaCl concentration increased from 1‰ to 15‰, respectively, compared with CK. With an increase in the NaHCO_(3)concentration from 0.5‰ to 8‰, NH_(3) volatilization increased by 8.36%–56.46%, 5.49%–30.10%, and 30.72%–73.18% at the N1, N2, and N3 levels, respectively, compared with CK. According to the SEM method, salinity and alkalinity had positive direct effects on NH_(3)volatilization, with standardized path coefficients of 0.40 and 0.19, *** the total effects(net positive and negative effects) in the SEM results, alkalinity had a greater influence than salinity(total standardized coefficien

关键词： alkalinity coastal ecosystem NH_(3)emission N-transforming microbe salinity structural equation modeling

A highoutput PDMS-MXene/gelatin triboelectric nanogenerator with the petal surface-microstructure

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Nano Research 2024年第5期17卷 4151-4162页

作者： Zekun Wang Congcong Hao Mingzhe Cai Juan Cui yongqiu Zheng Chenyang Xue Key Laboratory of Instrumentation Science&Dynamic Measurement Ministry of Education North University of ChinaTaiyuan 030051China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 611731China

Triboelectric nanogenerator(TENG)has a promising future in the field of energy harvesting and self-powered sensing due to their simplicity in structure,low cost,and efficient energy harvesting from the surrounding *** output electrical performance of TENG can be improved by doping the friction material with functional materials and modifying the surface of the friction ***,the current method of adding functional materials to friction materials is costly and wasteful,and the method of modifying the surface structure of friction materials is cumbersome and not easy to *** this work,we present a polydimethylsiloxane(PDMS)-MXene/gelatin triboelectric nanogenerator(PMMG-TENG)based on petal surface-microstructures,which has the advantages of low cost,simple preparation,high output performance,and ecological *** doping 0.03 wt.%of MXene in PDMS,the output electrical performance of TENG can be significantly improved,with an output current increase of up to 139.7%.Four different petals are used as natural molds to prepare *** results show that PMMG-TENG with peony petal surface microstructure has the best electrical performance,and the output current increase of up to 228.17%compared with PMMG-TENG without *** PMMG-TENG with peony petal surface-microstructure exhibits excellent electrical performance,demonstrating a maximum open-circuit voltage of 417.39 V and a maximum short-circuit current of 12.01μA at a size of 3 cm×3 cm,and a maximum power density of 170μW/cm^(2) at a load resistance of 107Ω.The PMMG-TENG’s output performance after 10,000 cycles is consistent with the initial state,highlighting excellent output *** PMMG-TENG can easily light up at least 100 light emitting diodes(LEDs).(operating voltage 3V.)Gelatin film exhibits excellent degradation performance,with complete degradation time of only 150 s in water at a constant temperature of 75℃.PMMG-TENG not only shows excellent performance in

关键词： triboelectric nanogenerator(TENG) petal surface-microstructure gelatin MXene energy harvesting

Discovery and character of the Kunlun-Yellow River Movement

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Chinese Science Bulletin 1998年第10期43卷 833-836页

作者： CUI Zhijiu 1, WU yongqiu 2,3 and liu Gengnian 1 1. Department of Geography, Peking University, Beijing 100871, China 2. Open Research Laboratory of Environmental Changes and Natural Disaster of State Education Commission, Beijing 100875, China Department of Geography Peking University Beijing China Open Research Laboratory of Environmental Changes and Natural Disaster of State Education Commission Beijing China Department of Geography Sichuan Normal Uni-versity Chengdu China

Based on geomorphological, tectonic and sedimentary data, a Kunlun Yellow River Tectonic Movement has been recognized in 1 10-0 60 Ma B.P. This tectonic movement, which leads to uplift of the Qinghai_Xizang (Tibet) Plateau from 1 500 to 3 000-3 500 m, is periodic, abrupt and changeable in the movement rate of uplifting and slide slipping.

关键词： Kunlun Mountain Pass 700 kaB.P. tectonic movement.

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基于运动控制器的雕刻机控制系统设计

机床与液压 2016年第2期44卷 191-194页

作者：刘勇求广东科技学院机电系广东东莞523083

传统的雕刻机系统开放性差、可移植性差,阻碍了雕刻机行业的发展。基于运动控制器设计雕刻机控制系统,分别介绍系统的硬件设计和软件设计。该控制系统具有良好的开放性,对雕刻机行业的发展具有一定的意义。

关键词：雕刻机控制系统运动控制器开放式系统

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飞行器运动控制建模及红外辐射图像仿真

红外技术 2020年第9期42卷 863-872页

作者：刘勇求金忠庆广东科技学院东莞523083 空军航空大学吉林长春130022

实时生成飞行器在飞行过程中的红外图像对于研究飞行器的红外特性具有重要意义。飞行器在飞行过程中,由于其飞行速度、高度、姿态等参数变化性较大,且机体本身容易受到环境、背景等辐射的影响,因此较难准确地仿真机体的温度场分布。由... 详细信息

实时生成飞行器在飞行过程中的红外图像对于研究飞行器的红外特性具有重要意义。飞行器在飞行过程中,由于其飞行速度、高度、姿态等参数变化性较大,且机体本身容易受到环境、背景等辐射的影响,因此较难准确地仿真机体的温度场分布。由于飞行器机体温度场分布与飞机的运动状态密切相关,因此文中首先建立了决定其姿态和速度的控制模型,并对飞行器面源热平衡方程进行建模研究。然后,应用CFD(Computational Fluid Dynamics)对飞行器的绝热壁温度场进行求解,并给出了机体绝热壁温度的高度简化算法。最后仿真了不同飞行器在不同波段、不同高度、不同速度下的红外图像。

关键词：红外图像面源热平衡方程 CFD 绝热壁温度

基于多故障鲁棒滑模重构观测器的蜂群无人机主动容错控制

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飞行力学 2023年第4期41卷 35-43页

作者：刘勇求刘晓峰广东科技学院广东东莞523083 空军航空大学吉林长春130000

针对蜂群无人机多种故障并发情形,提出综合鲁棒滑模故障重构观测器的主动容错控制策略。首先,构建链式长-僚机编队蜂群无人机多故障并发模型;然后,将传感器故障向量引入增维向量建立广义系统,提出蜂群无人机鲁棒滑模故障重构观测器设计... 详细信息

针对蜂群无人机多种故障并发情形,提出综合鲁棒滑模故障重构观测器的主动容错控制策略。首先,构建链式长-僚机编队蜂群无人机多故障并发模型;然后,将传感器故障向量引入增维向量建立广义系统,提出蜂群无人机鲁棒滑模故障重构观测器设计程式,引入线性矩阵不等式、自适应律等,给出观测器系数矩阵设计方案,确保蜂群无人机出现多未知故障、不确定扰动情形时,观测器状态重构误差快速收敛;最后,综合多故障同时重构程式给出蜂群无人机主动容错控制器设计方案,并通过仿真算例检验所提方法的有效性。

关键词：多故障滑模观测器故障重构主动容错

Fabrication， characterization， antihypertensive effect and potential mechanisms of a novel angiotensin I-converting enzyme inhibitory peptide derived from garlic by-products

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Food Science and Human Wellness 2024年

作者： Lu Xiang Zhenjia Zheng yongqiu Qi Haihua Chen Zhichang Qiu Xuguang Qiao Key Laboratory of Food Nutrition and Health in Universities of Shandong， College of Food Science and Engineering， Shandong Agricultural University College of Food Science and Engineering， Qingdao Agricultural University Department of Food Science， University of Massachusetts 102 Holdsworth Way， Amherst， Massachusetts 01003， United States

The valorisation of vegetable by-products is a promising strategy to combat climate change and achieve global carbon neutrality goals. This study aimed to exploit the high-value utilization of garlic by-products and to investigate the antihypertensive effects and potential mechanisms of the resulting angiotensin-converting enzyme （ACE）1inhibitory peptides. After protein extraction， enzymatic hydrolysis， and activity-directed fractionation， a potent and highly stable ACE inhibitory peptide (IC50value: 31.38 μmol/L) was obtained， which was identified as VWAS and acted as a competitive inhibitor. VWAS stably bound to key residues in the ACE active center mainly through hydrogen bonding interactions and effectively lowered blood pressure in spontaneously hypertensive rats via alleviating renal and cardiac injuries， improving endothelial dysfunction， and regulating the renal renin-angiotensin system， antioxidant system， and anti-inflammatory system. These findings suggested that garlic protein-derived peptide （VWAS） was a desirable candidate for antihypertensive functional foods and provided guidance for the high-value utilization of garlic by-products.

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基于阈值预警功能的高压开关柜光纤测温系统设计与测试

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实验室研究与探索 2017年第7期36卷 68-71页

作者：刘勇求王文斌广东科技学院机电工程系广东东莞523083 雅砻江流域水电开发有限公司成都610051

针对开关柜触点发热严重及温度难以精确检测的问题,对目前常用的测温技术进行分析对比,开发了基于阈值预警功能的高压开关柜光纤测温与预警系统。该系统以智能诊断与预警模块为核心,在实时检测被测点温度的同时,将检测结果与历史数据进... 详细信息

针对开关柜触点发热严重及温度难以精确检测的问题,对目前常用的测温技术进行分析对比,开发了基于阈值预警功能的高压开关柜光纤测温与预警系统。该系统以智能诊断与预警模块为核心,在实时检测被测点温度的同时,将检测结果与历史数据进行分析对比,当触点温度及其变化趋势接近或超过预警阈值时,系统自动发出警示。测试结果表明:该系统测温精度高,能有效用于开关柜内部温度的在线监测和预警,对工作人员实时掌握开关柜的运行状态,及时发现并处理故障隐患,保证开关柜安全运行提供依据。

关键词：开关柜预警光纤光栅在线测温